def dayup(df):
    dayup=1
    for i in range(365):
        if i % 7 in [6,0]:
            dayup=dayup*(1-0.01)
        else:
            dayup=dayup*(1+df)
    return dayup
dayfactor =0.01
while dayup(dayfactor)<37.78:
    dayfactor+=0.001